Vane slots for a fluid power converter

Abstract

In a fluid power converter, such as a hydraulic pump or motor, having a rotor and stator with vanes in both the rotor and stator, the improvement in the vane slots on one or both of the rotor and stator in which a ramp is provided on both sides of the open ends of each slot. The ramps are directed outwardly towards the annular space between the rotor and stator for allowing a crossing vane to cam out of the opposing slot thereby preventing the crossing vane from catching in the opposing slot.

What is claimed is: 
     
       1. In a fluid power converter having a rotor and a stator member, the members being concentrically mounted and rotatable one with respect to the other about a common center, said members having opposing peripheries contoured to provide an annular space therebetween, each of said peripheries including a plurality of spaced radially extending slots receiving a vane therein, each of said vanes having sides which are entirely straight a fluid inlet in the stator adjacent one side of each stator slot and opening into the annular space, a fluid outlet in the stator adjacent the second side of each stator slot and opening into the annular space, the improvement comprising, a ramp on at least one of the rotor and stator on the trailing sides of the open ends of each slot, said ramps being directed outwardly towards the annular space for allowing a crossing vane to cam out of the slot.   
     
     
       2. In a fluid power converter having a rotor and a stator member, the members being concentrically mounted and rotatable with respect to the other about a common center, said members having opposing peripheries contoured to provide an annular space therebetween, each of said peripheries including a plurality of spaced radially extending slots receiving a vane therein, the vanes in one of the members being thicker than the vanes in the other member each of said vanes having sides which are entirely straight, a fluid inlet in the stator adjacent one side of each slot and opening into the annular space, a fluid outlet in the stator adjacent the second side of each slot and opening into the annular space, the improvement comprising, a ramp on the member having the thicker vanes on both sides of the open end of each slot, said ramps being directed outwards towards the annular space for allowing a crossing thinner vane on the other member to cam out of the slot.   
     
     
       3. In a fluid power converter having a rotor and a stator member, the members being concentrically mounted and rotatable one with respect to the other about a common center, said members having opposing peripheries contoured to provide an annular space therebetween, each of said peripheries including a plurality of spaced radially extending slots receiving a vane therein, each of said vanes having sides which are entirely straight a fluid inlet in the stator adjacent one side of each stator slot and opening into the annular space, a fluid outlet in the stator adjacent the second side of each stator slot and opening into the annular space, the improvement comprising, a ramp on at least one of the rotor and stator on both sides of the open ends of each slot, said ramps being directed outwardly towards the annular space for allowing a crossing vane to cam out of the slot.   
     
     
       4. The apparatus of claim 3 wherein the slots on both the rotor and stator includes said ramps. 
     
     
       5. The apparatus of claim 3 wherein the ramps are flat and at an angle of approximately ten to ninety degrees to the longitudinal axis of said radially extending slots. 
     
     
       6. The apparatus of claim 3 wherein the ramps are rounded.